Induction-coil



(No Mode1,)

P. E. FISHER.

INDUCTION COIL.

No.'314,816. Patented Mar.31,1885.

lmetal (brass) in the form of a half-cylinder UNITED STATES FRANK FISHER, OF DETROIT, MICHIGAN.

INDUCTION-COIL.

SPECIFICATION forming part of Letters Application filed August 4, 1884.

To all whom it may concern:

Beit known that I, FRANK E. FIsHER, of Detroit, in the county of Wayne and State of Michigan, have invented a new and useful Improvement in Induction-Coils, of which the following is a specication.

Figure l is a vertical section, except the upper `end, which is in perspective. Fig. 2 is a section on the line :v Fig. l. Fig. 3 is an elevation of the movable diamagnetic cover, and Fig. 4 is avertical section through the induction-coil and vibrator as connected for use.

My invention relates to an improvement in movable diamagnetic covers for the cores Vof induction-coils, and is chiefly designed for use in medical batteries. It consists in a iixed diamagnetic cover partially surrounding the core and a movable diamagnetic cover adapted to revolve on the core as an axis and gradually cover or uncover the same, while at the same time the poles of the core are not interfered With.

H represents a wooden spool on which is wound an induction-coil, K, composed of a pri mary coil and a surrounding secondary coil of ner wire. This is a common electrical device,and needs no detailed description.

G represents a metal cap adapted to be screwed to a board on the top of a box which contains the complete device S, to hold the inductioncoil in position, and has a raised center, E, through which the upper end of the core of the induction-coil passes, and where said core is held in place by a nut, F.

@represents the core oi' the induction-coil, being arod of soft iron which passes through the center of the wooden spool H.

B represents a piece o'f thin diamagnetic soldered to core C, so that it covers one-half of said core from top to bottom of the coil.

A represents another piece of diamagnetic metal, which at its upper end is almost a complete cylinder, large enough to surround the core O and the diamagnetic piece B. Part of this piece A is cut away, as shown in Figs. 1 and 3,and I iind it best not to cut away a rectangular portion thereof, but to make a cut parallel with the axis of the piece A,which IY Patent No. 314,816, dated March 3l, 1885.

(No model.)

shall call the cylinder77 A, from end to end, and then to make another cut, which begins near the iirst cut at the upper end and then runs away from the first cut, so as to make about one-half turn in the length of the cylinder, leaving the cylinder A in the shape shown in Fig. 3. The upper end of cylinder A is fastened to a ring, a a, to which is secured a crank, D, which passes through and works in a slot in the raised center E of cap G.

L represents a vibrator secured at one end to the bindingpost R, the other end being in electrical or magnetic proximity to the upper pole, F, of core C, and the binding-post R Iis connected with the lower pole of the core Gby a piece oi' iron, I, as shown in Fig. 4. m represents a light spring secured to the vibrator L. N represents a metallic support, and O represents a contact-screw working in a thread ed hole in N.

The connections of the battery with the primary coil and the usual binding-posts to enable connection to be made with either the primary or secondary coil at pleasure are those commonly used in medical batteries,and do not need description or illustration. The action of the vibrator is also well understood7 and,as my invention is solely in the mechanism for covering and uncovering lthe core, I will only describe the operation of that part of the mechanism.

Vhen the crank D is turned into the position shown in Fig. 1,the cylinder Ais over the fixed piece B, and a portion of the core C is not surrounded by diamagnetic substance. The battery will now exert its maximum strength, because the core is exposed as much as is possible in my machine. By turning the crank D the exposed par-t of core C is gradually covered by the diamagnetic cylinder A, which revolves about the core until when the crank has been turned about one half-revolution the core G is completely surrounded by a diarnagnetic covering consisting of the fixed piece Band the cylinder A. The battery will now give its minimum effect.

By cutting the cylinder A in the manner shown and described it covers or uncovers the core gradually in approximately a longitudinal direction,and yet leaves both poles of the IOO core free to be utilized in Working the vibrator; and this construction has a decided effect in increasing the strength of current obtainable from a given battery, and also affords a simple and perfect means of regulating the current to any desired degree.

A simple mechanical equivalent for the construction herein shown and described,and one which I deem Within the spirit of my invention and the scope of the claims hereto anneXed, is to fasten the cylinder A and attach the crank to the core G, so that the core and xed piece B can be turned. This will expose the core C in the same manner as herein described.

What I claim as myinvention, and desire to secure by Letters Patent, is-

l. In an induction-coil, the combination of a soft-iron core, apiece of diamagnetic metal secured to and partially surrounding that part of the core which is within the coil, and a sec ond movable diamagnetic metal piece adapted to cover the remaining portion of said core within the coil,adapted to revolve on the core as an axis, and having an opening,` cut therein longitudinally of greater width at one end than at the other, substantially as shown and described.

2. The combination of theinductiou-coil K with the core C and the dia-magnetic metal pieces A B and the crank D, substantially as shown and described.

FRANK E. FISHER.

Vitnesses:

CYRUs E. IoTHRoP, SUMNER COLLINS. 

